1. Field of the Invention
This invention relates to idler trough roller assemblies which support the upper flights of belt conveyors for bulk materials. The roller assemblies include wing rollers extending upwardly and outward at each side, adapted to maintain the belt in a trough configuration. Intermediate central transverse rollers can be utilized between the wing rollers. This invention pertains to the structure of the wing rollers and their supports.
2. Description of the Prior Art
The general nature of troughed rollers for bulk material handling is described in U.S. Pat. No. 4,029,200 issued June 14, 1977 to Dillon. This patent discloses a lightweight enclosed plastic roller structure that receives stub shafts at each end.
U.S. Pat. No. 4,032,002, which was granted June 28, 1977 to Jackson describes cantilevered rollers for a trough conveyor idler assembly. The outer ends of the respective rollers are retained on support shafts that extend through the length of each roller. The roller assemblies are loosely mounted to enable individual rollers to tilt about a pivot axis in the forward direction relative to movement of the belt.
U.S. Pat. No. 3,545,602 which was granted on Dec. 8, 1970 to McCullagh describes rollers mounted on shafts in which the shafts have flattened sections at each end to enable the rollers to be easily mounted or removed for replacement purposes. Again, the support shafts extending through the rollers protrude beyond each roller end.
It is an object of this invention to improve upon the prior roller structures in trough roller assemblies by utilizing a cup-shaped roller made of plastic and requiring no internal bearings for support. The integral cup-shaped nature of the roller prevents entry of dirt or materials between the individual rollers and their respective support members.
Another object of this invention is to provide a roller assembly requiring a minimum number of parts, facilitating replacement of the rollers without disengaging any elements other than the rollers themselves.
These objects and others will be evident from the following disclosure.